A surface conditioner for silicon-based materials and its application in shaping and polishing

Abstract

The present invention discloses a surface finisher for silicon-based materials and its application in shaping and polishing, wherein the finisher comprises a workpiece and a processing fluid; the surface of the workpiece is coated with a catalyst layer; the catalyst layer comprises at least one of platinum, gold, nickel, iron and silver; and the processing fluid comprises water. The surface finisher for silicon-based materials developed by the present invention can achieve high surface accuracy and low surface roughness during the surface processing of optical elements, while avoiding sub-surface damage on the surface of the silicon-based material during the processing.

Description

Technical Field

[0001] The invention relates to the technical field of optical element processing, and in particular to a surface finisher for silicon-based materials and application thereof in shaping and polishing. Background Art

[0002] The development of aerospace, astronomical exploration, military, energy, medical and other fields has put forward higher requirements for the demand for optical components in ultra-precision components. Optical component materials represented by quartz crystal, quartz glass, microcrystalline glass, etc. have been widely used in optical imaging, high-power laser systems, laser nuclear fusion, solar cells, space observation, sensors, detectors and other fields. At present, optical components are required to have strict power spectral density (PSD) specifications to achieve low light scattering and high imaging performance. This means that the manufactured optical components not only require high surface accuracy and low surface roughness, but also require strict control of mid-spatial frequency (MSF) errors and subsurface damage (SSD).

[0003] At present, optical components represented by ion beam polishing (IBP), magnetorheological finishing (MRF), and computer controlled optical surface forming technology (CCOS) have led to the proposal of processing methods. Ion beam polishing uses the principle of ion beam sputtering to complete material removal processing. High-energy ion beams are obtained through accelerators and impact the material surface, so that most of the energy is transferred to atoms in the material layer. The impacted atoms also transfer energy to the surrounding atoms, generating atomic cascade motion, and the material atoms are sputtered and detached directly or due to multiple impacts. As a non-contact, atomic-level removal processing method, ion beam polishing does not produce residual stress on the processed surface. In order to generate ion beams and make the ions have a large free path, this method needs to be carried out in a vacuum environment. For large-sized workpiece tools, a vacuum chamber of corresponding size is often required to achieve processing, which limits the application of processing large-aperture optical components. In addition, due to the atomic-level removal resolution of this technology, its processing efficiency is low. Relevant literature has reported that the ion beam polishing method will introduce ion contamination problems on the surface of the processed material. Magnetorheological polishing technology mainly uses magnetorheological fluid and magnetic polishing disc for processing. Among them, the magnetorheological fluid is circulated by the polishing disc into the polishing area with a small gap between the workpiece tool and the polishing disc. In this area, the magnetorheological fluid undergoes rheological effect under the action of the high gradient magnetic field, and becomes hard and the viscosity increases. The magnetic particles in it are arranged into chains along the direction of the magnetic field strength, thereby forming a protruding ribbon with a certain shape. The polishing powder particles contained in the magnetorheological fluid are not magnetic, so they will be squeezed and float to the top of the weak magnetic field, forming a "flexible polishing mold" on the protruding ribbon. When the "flexible polishing mold" flows through the small gap formed by the workpiece tool and the moving disc under the drive of the moving disc, it will exert a large shear force on the surface, realizing the removal of the workpiece tool surface material. In principle, magnetorheological polishing technology is a contact processing method. Scratches will be introduced on the surface during the processing process, affecting the processing quality. Due to the limitation of the radius of the polishing wheel, magnetorheological technology is not suitable for processing surfaces with a small radius of curvature. Computer-controlled optical surface forming technology is based on traditional polishing technology, using a polishing disc that is much smaller than the workpiece tool diameter to achieve optical mirror processing. This technology uses computer-controlled polishing tools to accurately control the residence time and process parameters of the polishing disc at different positions of the workpiece tool to achieve accurate removal of optical component surface materials. It is a deterministic optical component processing method. The development of the small polishing disc CCOS technology has been relatively mature, but the technology still has some problems. With the wear of the polishing disc during processing, the long-term stability of the removal function is poor. The processing process requires a certain load to achieve mechanical shearing, and there will be sub-surface damage on the material surface.

[0004] Therefore, it is currently imperative to develop a surface finisher for silicon-based materials that can ensure high surface accuracy and low surface roughness during the surface processing of optical components, while avoiding sub-surface damage to the surface of silicon-based materials during the processing. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a surface finisher for silicon-based materials, which can achieve polishing of the surface of silicon-based materials to obtain a low-roughness surface of silicon-based materials without introducing surface and sub-surface damage on the surface of silicon-based materials. It can achieve precise shaping of the surface material of silicon-based materials.

[0006] The present invention also provides application of the above-mentioned trimmer in surface modification of silicon-based materials.

[0007] The present invention also provides application of the surface finisher for silicon-based materials in polishing the surface of silicon-based materials.

[0008] According to a first aspect of an embodiment of the present invention, a surface finisher for silicon-based materials comprises a workpiece processing tool and a processing fluid; the surface of the workpiece processing tool is coated with a catalyst layer; the catalyst layer comprises at least one of platinum, gold, nickel, iron and silver; the processing fluid comprises at least one of water and hydrofluoric acid.

[0009] A surface conditioner for silicon-based materials according to an embodiment of the present invention has at least the following beneficial effects:

[0010] In the surface finisher of silicon-based materials of the present invention, during the processing of silicon-based materials, the surface of the processing workpiece tool is coated with a catalyst layer (platinum Pt, etc.) material. During the processing, under the action of the catalyst layer, the processing fluid is hydrolyzed to generate hydroxyl radical groups attached to the surface of the silicon-based material, and then Pt-O-Si bonds are formed on the surfaces of Pt and the silicon-based material to obtain a 5-coordinated silicate structure. Due to the presence of the Pt-O-Si bond, the atomic bonding force between silicon and the base material of the silicon-based material is weakened. Under the continuous processing of the processing workpiece tool, the bonded silicon atoms are removed, and the reaction equation of the removal mechanism is as follows:

[0011]

[0012] According to the above material removal mechanism, without the action of the catalytic layer in the workpiece tool, the solution itself will not react with the silicon-based material. Therefore, during the processing, the removal of silicon-based materials is limited to the area where the catalytic layer acts, and the processing process belongs to deterministic processing. Since the atoms in the rough area of ​​the workpiece tool surface preferentially form covalent bonds with Pt atoms, they are preferentially removed during the processing process to obtain a surface with extremely low roughness. In the processing of silicon-based materials, there is no participation of abrasive particles, and the material removal mechanism is based on chemical action, so it will not cause sub-damage to the surface of the silicon-based material.

[0013] In addition, the surface finishing process of silicon-based materials only occurs in the area where the catalyst acts. Therefore, when the workpiece tool is processed at a fixed point, there is no contact and stress during the processing, the catalyst layer is not worn, and it will not be consumed due to the reaction. Under the above conditions, the size of the area where the surface finishing of the silicon-based material reacts is determined, and the reaction rate is constant, so the precise shaping of the surface material of the silicon-based material can be achieved.

[0014] The present invention utilizes at least one of water and hydrofluoric acid as a processing fluid, and no other processing fluid is introduced in the surface finishing of silicon-based materials, thereby avoiding pollution to the environment; when water is used as the processing fluid, the method utilizes a catalyst to promote the hydrolysis of the solution to form hydroxyl groups, so the material removal process is based on chemical action, the processing process does not require the participation of abrasive particles, and no sub-surface damage layer is generated.

[0015] According to some embodiments of the present invention, the processing fluid is provided at a rate of 0.1 L / min to 2 L / min.

[0016] According to some embodiments of the present invention, the workpiece processing tool includes at least one of a polishing disc, a polishing wheel and a polishing head.

[0017] According to some embodiments of the present invention, the silicon-based material includes at least one of silicon dioxide crystals, silicon carbide, and single crystal silicon.

[0018] The second aspect of the present invention provides a use of the trimmer in surface modification of silicon-based materials.

[0019] According to some embodiments of the present invention, the surface modification comprises the following steps:

[0020] A1. Measure the distribution function Z(x, y) of the amount of silicon-based material to be removed;

[0021] The removal amount per unit time of the trimmer and the silicon-based material is measured; and the removal amount per unit time is obtained according to the removal amount per unit time.

[0022] To remove the function R(x,y);

[0023] A2. Obtaining a distribution function T(x, y) of the residence time according to the distribution function of the amount to be removed and the removal function.

[0024] The calculation method is shown in formula (I), where represents convolution calculation; obtaining a processing path code through the distribution function of the residence time;

[0025]

[0026] A3. Import the processing path code into a numerical control processing system and then process the silicon-based material.

[0027] According to some embodiments of the present invention, the method for testing the distribution function of the amount to be removed is to perform difference calculation between the ideal surface parameters of the silicon-based material and the actual surface parameters of the silicon-based material.

[0028] The principle of surface modification of silicon-based materials is as follows: when the workpiece tool is used for fixed-point processing, there is no contact and stress between the workpiece tool and the surface of the silicon-based material during the processing, so the catalyst layer is not worn and will not be consumed by the reaction. Under the above conditions, the size of the reaction area is determined, the reaction rate is constant, and the material removal distribution in the interaction area between the workpiece tool and the silicon-based material surface per unit time remains stable, that is, the range, depth and shape of the action on the silicon-based material surface are determined (the material removal spot is stable), so a stable distribution function of the amount to be removed Z(x,y) (the ratio of the removal spot to the processing time) can be obtained on the workpiece tool surface. In the process of surface modification of silicon-based materials, the surface removal amount of silicon-based materials is directly proportional to time. A stable removal function means that as long as the processing parameters (such as processing time) can be controlled, the material removal amount can be controlled. Therefore, by adjusting the residence time of the workpiece tool at each point on the surface of the silicon-based material, the differentiated modification of the surface of the silicon-based material at different positions can be achieved (in layman's terms, the residence time at the relatively high point of the workpiece tool is long, and the residence time at the relatively concave point is short, so that the surface of the workpiece tool is finally flat), and finally the purpose of high-precision surface shape control processing is achieved.

[0029] To modify the surface of silicon-based materials, first use a surface measurement instrument to detect the initial surface shape of the workpiece tool, and compare it with the ideal surface shape (design surface shape) to obtain the distribution function Z(x, y) of the amount to be removed at each point on the surface of the workpiece tool; combine the amount to be removed at each point on the surface of the silicon-based material and the distribution function Z(x, y) of the amount to be removed, and calculate through the residence time algorithm to obtain the residence time distribution of the processing workpiece tool at each point on the surface of the silicon-based material; further convert the residence time of each point into the movement speed of the processing workpiece tool, and derive the corresponding grating processing path code, that is, the CNC machine tool G code; finally, run the corresponding grating processing path code on the CNC processing system for processing to achieve the modification of the surface shape of the silicon-based material. The core issue of the modification processing is the relationship between the distribution function Z(x, y) of the amount to be removed at each point, the removal function R(x, y), and the distribution function T(x, y) of the residence time. Since the workpiece processing tool is continuously moving on the surface of the silicon-based material, the removal amount at a certain position is equal to the sum of the material removal amounts caused by the workpiece processing tool at that position during the surface scanning process of the silicon-based material. Scanning refers to the processing of the silicon-based material by the workpiece processing tool. It is not a process of staying at a certain place for a period of time for processing, but a process of continuous movement. That is, scanning processing refers to the continuous processing of different positions of the workpiece tool by the workpiece processing tool at a certain movement speed. Therefore, the mathematical relationship between the removal amount distribution function Z(x,y), the removal function R(x,y) and the distribution function of the residence time T(x,y) is described as: the removal amount distribution function Z(x,y) is the convolution of the removal function R(x,y) and the distribution function of the residence time T(x,y). Its mathematical expression is:

[0030]

[0031] Wherein Z(x, y) can be measured by a surface measurement instrument, and R(x, y) can be obtained by testing the removal amount per unit time of the trimmer and the silicon-based material; Represents convolution calculation. Therefore, the solution process of T(x,y) is essentially the process of deconvolution of Z(x,y) and R(x,y) at each point.

[0032] According to some embodiments of the present invention, the deconvolution process includes a linear equations method and a pulse iteration method.

[0033] The deconvolution algorithms used are the linear equations method and the pulse iteration method:

[0034] Principle of the method of linear equations:

[0035] Discretize the surface shape, and there are error points and processing points in the processing process. The error point is the distribution of the surface shape error obtained by the detection device and corresponds to the distribution point of the removal amount, recorded as (xi, yi), with a total of m points; the processing point is the resident processing point in the calculation and processing process, recorded as (pj, qj), with a total of n points. Then the removal amount for the error point (xi, yi) is the removal of it by all resident points (pj, qj), and the expression is as follows:

[0036]

[0037] Where Tj is the dwell time of the jth processing point, and Rij is the amount of removal of the ith error point by the jth processing point. Usually, in order to find a suitable non-negative dwell time, the number of error points should be greater than the number of processing points, that is, m>n. The matrix equation shown above is an overdetermined linear equation system. The non-negative least squares solution of the equation can be used to find the dwell time that minimizes the RMS of the post-processing shape error.

[0038] Principle of pulse iteration method:

[0039] When solving the residence time, usually the location with large removal amount has a long residence time, so the residence time distribution can be fitted by the distribution of removal amount, which is calculated as follows:

[0040]

[0041] Where T k is the residence time calculated at the kth iteration, E k is the surface shape error calculated at the kth iteration, It is the relaxation factor. The larger it is, the faster the convergence will be. However, if it is too large, it will easily diverge. It is generally less than 1.

[0042] After each iteration, the RMS value of the surface error is calculated. When the RMS value does not decrease with the number of iterations, the iteration is stopped to obtain a better dwell time value. Specifically, if the residual error is positive, it means that the dwell time is insufficient, and the dwell time is increased proportionally. If the residual error is negative, it means that the dwell time is too large, and the dwell time is reduced proportionally. Due to the existence of the relaxation factor, the change in each dwell time becomes smaller and smaller, and a converged result is obtained.

[0043] The material removal area of ​​this method is limited to the catalyst action area, which belongs to deterministic processing. According to the needs, processing tools of different shapes and sizes can be designed for polishing and shaping. The size of the processing tool can be designed accordingly according to the size of the silicon-based material.

[0044] According to some embodiments of the present invention, polishing tools of different shapes are designed for processing. The removal function generated by polishing tools of different shapes may be different, but the shaping and polishing principles of the workpiece tool are the same, so the method of designing different polishing tools based on the material removal principle and shaping concept in the method of the present invention should still be covered by the solution of the present invention.

[0045] According to some embodiments of the present invention, the actual surface parameters of the silicon-based material are tested by an instrument.

[0046] According to some embodiments of the invention, the instrument comprises a laser interferometer.

[0047] According to some embodiments of the present invention, the application in the surface modification of silicon-based materials also includes detecting actual surface parameters of the silicon-based material after step A3, and if the actual surface parameters of the silicon-based material do not meet the interference measurement requirements, entering steps A1 and A2.

[0048] The surface finisher of the optical element of the present invention does not require a vacuum environment when modifying the surface of the optical element, and is easy to operate.

[0049] A third aspect of the present invention provides an application of a surface conditioner in polishing a silicon-based material surface.

[0050] According to some embodiments of the present invention, the surface conditioner is used in surface polishing of silicon-based materials, and the surface polishing includes the following steps: polishing the surface of the silicon-based material with the conditioner, the rotation speed of the workpiece processing tool is 0~5000rpm; the polishing time is 20min~300min.

[0051] According to some embodiments of the present invention, the application of the surface conditioner in polishing the surface of silicon-based materials also includes detecting the roughness of the silicon-based material. If the roughness of the silicon-based material does not meet the interference measurement requirements, the surface of the silicon-based material is polished again with the conditioner.

[0052] According to some embodiments of the present invention, the use of the surface conditioner in the surface modification of silicon-based materials further includes removing impurities from the tool for processing the workpiece before detecting the surface shape.

[0053] According to some embodiments of the present invention, the removing of impurities includes cleaning and removing of impurities.

[0054] According to some embodiments of the present invention, the cleaning method includes ultrasonic cleaning.

[0055] According to some embodiments of the present invention, the use of the surface conditioner in polishing the surface of a silicon-based material further comprises cleaning the processing tool of the workpiece after the polishing.

[0056] According to some embodiments of the present invention, the cleaning method includes ultrasonic cleaning. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0058] Figure 1 is the processing mechanism of the surface conditioner of silicon-based material of Examples 2 and 4 of the present invention;

[0059] Figure 2 is the processing mechanism of the surface conditioner of silicon-based material of Examples 2 and 4 of the present invention;

[0060] Figure 3 is the processing mechanism of the surface conditioner of silicon-based material of Examples 2 and 4 of the present invention;

[0061] Figure 4 This is a schematic diagram of the surface finisher of silicon-based materials in Example 2 of the present invention for polishing the surface of silicon-based materials;

[0062] Figure 5 The roughness detection of the surface conditioner of the silicon-based material of the embodiment 2 of the present invention before the surface of the silicon-based material is polished;

[0063] Figure 6 The surface finisher of the silicon-based material of Example 2 of the present invention detects the roughness of the silicon-based material surface after polishing;

[0064] Figure 7 is a flow chart of a method for polishing a silicon-based material surface by a surface conditioner for silicon-based materials according to Example 2 of the present invention;

[0065] Figure 8 is a schematic diagram of a surface conditioner for silicon-based materials provided in Examples 1 and 3;

[0066] Fig. 9 is a flow chart of a method for modifying the surface of a silicon-based material by a surface conditioner for a silicon-based material according to Example 4 of the present invention;

[0067] Fig.10 is the residual error obtained by simulating the surface modification of the silicon-based material by the surface modifier of the silicon-based material according to the fourth embodiment of the present invention;

[0068] Fig.11 is the residual error obtained by simulating the surface modification of the silicon-based material by the surface modifier of the silicon-based material according to the fourth embodiment of the present invention;

[0069] Fig.12 is the residual error obtained by the surface conditioner of the silicon-based material according to the fourth embodiment of the present invention after the actual processing of the surface modification of the silicon-based material;

[0070] Fig.13 When the workpiece processing tool 104 in Embodiments 1 and 3 is a polishing disc;

[0071] Fig.14 When the workpiece processing tool 104 in Embodiments 1 and 3 is a polishing head;

[0072] Reference numerals: machining liquid supply device (solution supply) 105 ; machining workpiece tool 104 ; fixing plate 106 ; to-be-machined workpiece tool 107 ; machining workpiece tool rotation axis 108 ; support portion 110 ; base 101 ; vertical rod 102 ; first crossbar 103 . DETAILED DESCRIPTION

[0073] The embodiments of the present invention are described in detail below, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below by reference are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention. The method can change the type and size of the trimmer according to the shape and size of the silicon-based material to achieve surface trimming of the silicon-based material.

[0074] In the description of the present invention, if there is a description of first, second, etc., it is only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0075] In the description of the present invention, it should be noted that, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention in combination with the specific content of the technical solution.

[0076] Example 1

[0077] This embodiment provides a surface conditioner for silicon-based materials, the structure of which is as follows: Figure 8 As shown, including:

[0078] The support part 110 is provided with a base 101, a vertical rod 102 and a first crossbar 103; one end of the vertical rod 102 is vertically connected to the base 101, and the other end is vertically connected to the first crossbar 103;

[0079] A workpiece processing tool 104, wherein the workpiece processing tool 104 is connected to an end of the first crossbar 103 away from the vertical bar 102;

[0080] A fixed plate 106, the fixed plate 106 is used to fix the workpiece tool 107 to make the workpiece tool 107 contact with the workpiece processing tool 104;

[0081] A workpiece processing tool rotation axis 108, which is vertically connected to the center of the fixed disk 106, and is used to provide rotation for the fixed disk 106, or stop the rotation operation;

[0082] It can be understood that the first crossbar 103 can move up and down along the vertical bar 102; the vertical bar 102 can move along the support portion 110;

[0083] In this embodiment, the processing mechanism of the surface conditioner is as follows: Figures 1 to 3 As shown,

[0084] It is further understood that the surface of the workpiece processing tool 104 is coated with a catalyst layer of platinum.

[0085] The machining fluid in the machining fluid supply device 105 is water.

[0086] In this embodiment, when the workpiece processing tool 104 is a polishing disk, Fig.13 As shown;

[0087] When the workpiece processing tool 104 in this embodiment is a polishing wheel, Fig.14 shown.

[0088] Example 2

[0089] The present invention provides an application of a silicon-based material surface conditioner in Example 1 in polishing the surface of a silicon-based material. The flow chart of the method for polishing the surface of a silicon-based material by using the silicon-based material surface conditioner is as follows: Figure 7 As shown, the polishing mechanism is as follows Figure 4 As shown, the specific steps are:

[0090] S1. Place the silicon-based material (workpiece tool) on the surface of single crystal silicon of size 15mm*15mm on the surface dresser and perform the polishing process. The polishing time is 4h, the polishing disc substrate speed is set to 20r / min, the water outlet speed is 0.15L / min, and the catalyst layer is platinum.

[0091] S2. After polishing, take it out and perform ultrasonic cleaning. Use white light interferometer to detect the surface roughness after polishing. Figure 5 , Figure 6 The results are shown. It can be seen from the figure that the surface roughness of the workpiece tool surface is 5μm*5μm ( Figure 6 ) value dropped to 0.0517nm, and the surface roughness of 1μm*1μm ( Figure 5 ) value dropped to 0.0376nm, so the obtained silicon-based material has extremely high precision and achieves sub-nanometer polishing, which meets the processing requirements and the processing is completed.

[0092] Example 3

[0093] This embodiment provides a surface conditioner for silicon-based materials, the structure of which is as follows: Figure 8 As shown, including:

[0094] The support part 110 is provided with a base 101, a vertical rod 102 and a first crossbar 103; one end of the vertical rod 102 is vertically connected to the base 101, and the other end is vertically connected to the first crossbar 103;

[0095] A workpiece processing tool 104, wherein the workpiece processing tool 104 is connected to an end of the first crossbar 103 away from the vertical bar 102;

[0096] A fixed plate 106, the fixed plate 106 is used to fix the workpiece tool 107 to make the workpiece tool 107 contact with the workpiece processing tool 104;

[0097] A workpiece processing tool rotation axis 108, which is vertically connected to the center of the fixed disk 106, and is used to provide rotation for the fixed disk 106, or stop the rotation operation;

[0098] It can be understood that the first crossbar 103 can move up and down along the vertical bar 102; the vertical bar 102 can move along the support portion 110;

[0099] In this embodiment, the processing mechanism of the surface conditioner is as follows: Figures 1 to 3 As shown,

[0100] It is further understood that the surface of the workpiece processing tool 104 is coated with a catalyst layer.

[0101] The machining fluid in the machining fluid supply device 105 is water;

[0102] In this embodiment, when the workpiece processing tool 104 is a polishing disk, Fig.13 As shown;

[0103] In this embodiment, when the workpiece processing tool 104 is a polishing disk, Fig.14 shown.

[0104] Example 4

[0105] The present invention provides an application of a silicon-based material surface conditioner in Example 3 in silicon-based material surface modification. The method flow chart of this embodiment is as follows: Fig. 9 As shown, the specific steps are:

[0106] S1. Trim the surface of a 15mm*15mm single crystal silicon, clean it ultrasonically, and then put it into a laser interferometer to detect the surface shape to obtain surface shape data. Perform difference calculation based on the ideal surface shape parameters and the actually measured surface shape data, set the target surface shape to an ideal plane, set the additional removal amount to 2.5nm, and obtain the removal amount distribution data (distribution function of the amount to be removed Z(x,y)).

[0107] S2. Etch the silicon surface for 1 min under the condition that the solution is pure water and the catalyst layer is Pt, calculate the removal amount, and obtain the removal function, that is, calibrate the removal amount for 1 min to obtain the removal function. According to the distribution characteristics of the surface error, the algorithm selected is the pulse iteration method through computer simulation calculation.

[0108] S3. Calculate the dwell time: According to the surface error distribution and removal function, the pulse iteration algorithm is used to perform computer simulation calculation to obtain the dwell time distribution. The grating processing path code is obtained from the dwell time. Check the simulation results. The residual error obtained by simulation is as follows: Fig.10 and Fig.11 shown.

[0109] S4, put the sample to be processed into the device, import the generated processing code into the CNC processing system, and process it. The total processing time is 116 minutes. After processing, ultrasonic cleaning is performed and the surface shape is tested again. The surface shape obtained is as follows Fig.12 shown.

[0110] After simulating the machining process, the PV value of the surface shape in the machining area of ​​15mm*15mm is below 4nm, and the RMS value is 0.34nm. Since the contact area between the catalyst layer and the machining sample is only half of the inner machining area at the edge of the machining area, it will affect the flow state of the solution. At the same time, due to the change of the contact surface, the removal rate also changes. The simulation results will be quite different from the actual machining results. Therefore, the evaluation area needs to be reduced to 14mm*14mm area. The PV value of the 14mm*14mm area is below 2nm, and the RMS value is 0.28nm. Compared with the original surface shape, the RMS convergence ratio of the simulation results reached 61.86, which has a good effect and can basically meet the requirements. The machining is completed.

[0111] Comparative Example 1

[0112] This comparative example provides a surface conditioner for silicon-based materials. The difference between this comparative example and Example 3 is that the surface of the workpiece processing tool 104 in Example 1 is not coated with a catalyst layer of platinum, and the other conditions are the same as those in Example 3.

[0113] Comparative Example 2

[0114] This comparative example provides a surface conditioner for silicon-based materials. The difference between this comparative example and Example 4 is that a surface conditioner for silicon-based materials in Comparative Example 1 is used in surface modification of silicon-based materials, and the other conditions are the same as those in Example 4.

[0115] Under this condition, as the workpiece tool wears during the machining process, the removal function cannot remain stable for a long time. Therefore, it is impossible to combine computer-aided control technology to achieve accurate removal of surface material and thus realize reshaping processing.

[0116] Comparative Example 3

[0117] This comparative example provides a surface conditioner of a silicon-based material. The difference between this comparative example and Example 1 is that the surface of the workpiece processing tool 104 in Example 1 is not coated with a catalyst layer of platinum, and the other conditions are the same as those in Example 1.

[0118] Comparative Example 4

[0119] This comparative example provides a surface conditioner for silicon-based materials. The difference between this comparative example and Example 2 is that a surface conditioner for silicon-based materials in Comparative Example 1 is used in the surface modification of silicon-based materials, and the other conditions are the same as those in Example 2.

[0120] Under this condition, the surface of the tool for processing the workpiece is not coated with a catalyst, so it is impossible to achieve the hydrolysis of the processing fluid under the action of the catalyst layer to produce hydroxyl free radical groups attached to the surface of the silicon-based material, and then form Pt-O-Si bonds on the surface of the Pt and silicon-based materials, thereby achieving surface polishing of the tool for the workpiece to be processed.

[0121] The above is a detailed description of the embodiments of the present invention, but the present invention is not limited to the above embodiments. Various changes can be made within the knowledge of ordinary technicians in the relevant technical field without departing from the purpose of the present invention. In addition, the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

Claims

1. Application of a trimmer in surface modification of silicon-based materials, characterized in that: The trimmer includes a processing tool and a processing fluid; The surface of the processing tool is coated with a catalyst layer; The catalyst layer includes at least one of platinum, gold, nickel, iron and silver; The processing fluid includes at least one of water and hydrofluoric acid; The silicon-based material includes at least one of silicon dioxide crystal, silicon carbide and single crystal silicon; The surface modification comprises the following steps: A1. Measure the distribution function Z(x, y) of the amount of silicon-based material to be removed; The removal amount per unit time of the trimmer and the silicon-based material is measured; and a removal function R(x, y) is obtained according to the removal amount per unit time; A2. Obtaining a distribution function T(x, y) of the residence time according to the distribution function of the amount to be removed and the removal function. The calculation method is shown in reference formula (I), wherein V represents convolution calculation; the processing path code is obtained through the distribution function of the residence time; Z(x,y)=R(x,y)VT(x,y)(Ⅰ); A3. Import the processing path code into a numerical control processing system and then process the silicon-based material.

2. The use according to claim 1, characterized in that: The method for testing the distribution function of the amount to be removed is to perform difference calculation between the ideal surface shape parameters of the silicon-based material and the actual surface shape parameters of the silicon-based material.

3. The use according to claim 2, characterized in that: The actual surface parameters of the silicon-based material are tested by an instrument; the instrument includes a laser interferometer.

4. The use according to claim 2, characterized in that: The application further includes detecting actual surface parameters of the silicon-based material after step A3, and if the actual surface parameters of the silicon-based material do not meet the interference measurement requirements, proceeding to steps A1 and A2.

Images